1. Field of the Invention
This invention relates to a wiper drive system for use in a road vehicle and, more particularly, to such a wiper drive system including an intermittent motion control device for intermittently connecting a wiper drive motor to a power source.
2. Description of the Prior Art
It is known that for a particular density of rain, the amount of rain dropping on a road vehicle window glass increases with increasing vehicle running speed. Wiper drive systems have been proposed which include a wiper intermittent motion control device manually operable to control the period of intermittent motion of wiper blades. However, such conventional systems require the vehicle operator to operate the wiper intermittent motion control device each time the vehicle stops or starts running, or shifts into a low or high running speed.
Therefore, the present invention provides a wiper intermittent motion control device which can automatically control the period of intermittent motion of wiper blades in accordance with vehicle running speed.